68 . Chemistry. Lecture. 26. 



of heat, and the point at which they become 

 fluid is still a settled one. 



This point is called their melting point, which 

 in the undermentioned substances is as follows : 

 Lead - 594 Milk 30 



Bismuth 576 Vinegar - 28 

 Tin 442 Blood $5 



Sulphur 212 Oil of bergamot 23 



Wax - 142 Wines - 20 

 Spermaceti 133 Oil of turpentine 14 

 Phosphorus 100 Sulphuric acid 36 below O. 

 Tallow - 92 Mercury - 39 

 Oil of anise 50 Liquid ammonia 46 

 Olive oil - 36 Ether 46 



Ice - - 32 Nitric acid 66 



In general those solid bodies which crystallize 

 have no interval between solidity and fluidity, 

 while those which do not assume the crystallized 

 form exhibit that gradual softening which I just 

 now remarked. 



Some bodies, after having appeared in a fluid 

 state by means of heat, concrete again into the 

 same form as before they were melted, as salt, ice, 

 the metals, especially gold and silver ; the melt- 

 ing of these bodies is called fusion. There are 

 other bodies, as earths, stones, oxides of metals, 

 which suffer alteration and concrete into masses 

 like glass, of a hard and brittle nature, and whose 

 particles, when broken, have hard and polished 

 surfaces. The making of this glassy concretion 

 is called vitrification. 



Fluidity has hitherto been considered as de- 



